Wear work gloves when you inspect the chainsaw’s cutting equipment.
Make sure the chain is correctly tensioned. A slack chain may jump off the guide bar, injure you and damage the chainsaw. An overly tight chain tension can cause premature wear of the guide bar. A properly tensioned chain should not hang under the guide bar. The chain tension is correct when the chain is in contact with the underside of the guide bar, and you still can pull it around easily by hand. See picture above.
A sharp chain
The chain must always be sharp to ensure cutting that is safe, effective and has good precision. An easy way to keep the chain sharp is to use the Husqvarna filing gauge and follow the filing instructions in the following sections.
How often should the chain be sharpened?
A saw chain's sharpness is impaired after time even if you have been avoiding cutting into objects that reduce its sharpness (rock, soil etc.). The chain becomes blunt. If the chain has sawn through stone it is useless and must be sharpened immediately. If you use a chainsaw for much of the day, it is appropriate to sharpen the chain with a file each time you refuel. It is easier to sharpen a little but often than waiting a long time to file. You also get better precision and work more efficiently.
Click to enlarge
Always use the type of guide bar and chain recommended by the manufacturer. The table shows the various chain types and round file sizes for Husqvarna Chains and corresponding Oregon Chains.
Here you can see how it looks when a cutting tooth is blunt. It is high time to sharpen the cutting teeth. Notice the cutting tooth’s “white” edge.
Backward leaning angle. The cutting tooth is filed too high up, making it cut poorly. Use the depth gauge and re-file the cutting teeth according to the recommendation.
A cutting tooth that has sawn through stone shows an irregular edge where the top layer of the cutting tooth is damaged. It is important that all the damage is filed away to ensure the best possible sharpness.
This is what a sharp cutting tooth looks like.